Display controller for display device of vehicle

ABSTRACT

A display screen switches between a monitor display and a trouble display. If a pause switch on the trouble display is operated, the display screen will be fixed to the trouble display for a prescribed time. The display screen can be set to the trouble display until a restart or release switch on the trouble display screen is operated. The monitor display and the trouble display can be cyclically displayed. During cyclical display, a jump switch on the trouble display can be operated, so that the display device will be returned to the monitor display from the trouble display, where the monitor display can be displayed for a prescribed time (for instance, 5 minutes). In addition, a cancel switch on the trouble display can be operated, so that the display screen may be kept returned to the monitor display.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part application of U.S.Ser. No. 10/053,960, filed Jan. 24, 2002, which is pending.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a display device provided in adriver's room of a vehicle such as a construction machine to display theconditions of respective parts of the vehicle and an abnormality such asa failure generated in the vehicle and more particularly to a displaycontroller for the display device for controlling the contents of thedisplay of the display device.

[0004] 2. Description of the Related Art

[0005] Generally, a display device for displaying the state of aconstruction machine such as cooling water and an abnormality such as afailure including the deterioration of oil pressure of an engine isprovided in the driver's room of the construction machine. This displaydevice is called a monitor panel.

[0006] The display screens of a conventional monitor panel areillustrated in FIGS. 1(a), 1(b) and 1(c).

[0007] FIGS. 1(a), 1(b) and 1(c) shows monitor screens 11, 12 and 13 formonitoring and displaying the operating states of a constructionmachine.

[0008] On the monitor panel, prescribed positions of the displayedscreens 11, 12 and 13 are touched so that the states of the displayscreens can be shifted to other states.

[0009] Specifically, when an engine key is switched on to turn on apower, the display screen of the monitor panel is shifted to a monitordisplay screen shown in FIG. 1(a) via an initial screen.

[0010] The states of respective parts such as the amount of remainingfuel of an engine of the construction machine, the temperature ofhydraulic oil of a working machine, the temperature of coolant of theengine, the oil pressure of the engine, etc. are detected by sensorsprovided in the respective parts of the construction machine. A signaldetected by each sensor is inputted to the monitor panel. Then, on themonitor panel, the current state of the construction machine isdisplayed on the monitor display screen on the basis of the signalsdetected by the sensors.

[0011] As shown in FIG. 1(a), on the monitor display screen 11 areprovided a display part 11 a for displaying the amount of currentlyremaining fuel, a display part lib for displaying the currenttemperature of the hydraulic oil of the working machine, a display part11 c for displaying the current temperature of the coolant of theengine, a display part 11 d for displaying the current oil pressure ofthe engine, etc. An operator visually recognizes the display parts 11 ato 11 d of the monitor display screen 11 so that the operator canrecognize the conditions of the respective parts of the constructionmachine.

[0012] When a button 11 e on the monitor display screen 11 is operated,the monitor display screen 11 is shifted to a next monitor displayscreen 12 shown in FIG. 1(b). Further, when a button 12 e on the monitordisplay screen 12 is operated, the monitor display screen 12 is shiftedto a next monitor display screen 13 shown in FIG. 1(c). Further, when abutton 13 e on the monitor display screen 13 is operated, the monitordisplay screen 13 is returned to the first monitor screen 11 shown inFIG. 1(a). If the same operations are carried out after that, the sametransitions will be repeated. As described above, the monitor displayscreens are sequentially and cyclically shifted from 11 and 12 to 13, sothat all the states of the construction machine can be recognized.

[0013] When the detected value of each sensor provided in each part ofthe construction machine reaches an abnormal value, an error codecorresponding to the abnormality is generated in a controller in thevehicle and the display screen of the monitor panel is automaticallyshifted to a trouble display screen for displaying a trouble such as afailure from the monitor display screen shown in FIGS. 1(a), 1(b) and1(c).

[0014] For instance, when a trouble or problem such as a failure isgenerated in a pump controller during the display of the monitor displayscreen 11 shown in FIG. 1(a) on the monitor panel, the monitor displayscreen 11 is shifted to a trouble display screen 21 shown in FIG. 2(a).In the trouble display screen 21, a trouble showing the contents of“Problem pump controller” is displayed. The operator visually recognizesthe trouble display of the trouble display screen 21 so that theoperator can recognize the trouble generated in the constructionmachine.

[0015] The monitor display screen 11 shown in FIG. 1(a) and the troubledisplay screen 21 shown in FIG. 2(a) are alternately displayed atprescribed intervals, for example, at intervals of 5 seconds. Thus,while the operator recognizes the contents of the trouble generated inthe construction machine, he can continuously perform the operation ofthe construction machine.

[0016] In the construction machine, a plurality of problems or troublesmay be possibly generated at the same time. For instance, three kinds oftroubles may be generated. If three kinds of troubles (called them afirst trouble, a second trouble and a third trouble, hereinafter) aregenerated while the monitor display screen 11 shown in FIG. 1(a) isdisplayed on the monitor panel, the monitor display screen 11, the firsttrouble display screen 21 on which the first trouble is displayed, asecond trouble display screen 22 on which the second trouble isdisplayed and a third trouble display screen 23 on which the thirdtrouble is displayed will be cyclically displayed as shown in FIG. 4. Inother words, the monitor display screen 11, the first trouble displayscreen 21, the second trouble display screen 22 and the third troubledisplay screen 23 are displayed at intervals of, for instance, 5seconds.

[0017] As described above, when a trouble is generated in theconstruction machine, the monitor display screen 11 and the troubledisplay screen 21 are alternately displayed, or the monitor displayscreen 11 and the trouble display screens 21, 22 and 23 are cyclicallydisplayed. Therefore, the operator needs to recognize the contents ofthe display of the trouble display screen 21 in a short time (forinstance, 5 seconds). Accordingly, the operator cannot sufficientlyrecognize the contents of the display of the trouble display screen 21.

[0018] Further, the operator may, sometimes, have a desire to completelyrecognize not the trouble display screen 11, but the monitor displayscreen 11. Still further, the operator may have a desire to sufficientlyrecognize not the display screen which is currently displayed, but adisplay screen which will be displayed or the display screen which hasbeen already displayed.

[0019] Still further, even when a trouble is generated, the operator ofthe construction machine needs to continuously operate and manipulatethe construction machine by paying his attention to the trouble.

[0020] However, since the monitor screen 11 and the trouble displayscreen 21 are alternately displayed, or the monitor display screen 11,and the trouble display screens 21, 22 and 23 are cyclically displayed,the operator can, undesirably, continuously and visually recognize thecontents of the display of the monitor display screen 11 only for ashort time (for instance, 5 seconds). Further, when a plurality oftrouble display screens are displayed, the monitor display screen 11cannot be visually recognized for a long time when the trouble displayscreens 21, 22 and 23 are displayed. Therefore, the state of theconstruction machine cannot be completely grasped so that there exists afear that a trouble may arise in operating and manipulating theconstruction machine.

[0021] Further, when the plural monitor display screens are sequentiallydisplayed, the operator may have, sometimes a desire to return thedisplay screen to a specific monitor display screen to completelyrecognize the operating state of the vehicle which he specially wants toknow.

[0022] Still further, the operator may have, sometimes, a desire toreturn the display screen not to the monitor display screen, but to thetrouble display screen so as to completely recognize the contents of thetrouble of the vehicle.

SUMMARY OF THE INVENTION

[0023] The present invention was proposed by taking the above-describedcircumstances into consideration and it is a first object of the presentinvention to provide a display controller for a display device of avehicle in which the contents of a specific display screen can becompletely grasped even when a trouble is generated in the vehicle of aconstruction machine and a monitor display screen and a trouble displayscreen are sequentially displayed or a plurality of monitor displayscreens are sequentially displayed so that one display screen isdisplayed only for a short period.

[0024] It is a second object of the present invention to provide adisplay controller for a display device of a vehicle in which, a displayscreen can be returned to one monitor display screen to sufficientlyrecognize the operating state of the vehicle even when a trouble isgenerated in the vehicle of a construction machine or the like and amonitor display screen and a trouble display screen are sequentiallydisplayed or a plurality of monitor display screens are sequentiallydisplayed so that one monitor screen is displayed only for a shortperiod, and a display screen can be returned to one trouble displayscreen to sufficiently grasp the contents of the trouble of the vehicleeven when a trouble is generated in the vehicle of the constructionmachine or the like and the monitor display screen and the troubledisplay screen are sequentially displayed so that one trouble displayscreen is displayed only for a short period.

[0025] Thus, in order to achieve the first object, according to a firstaspect of the present invention, there is provided a display controllerfor a display device of a vehicle having the display device fordisplaying a display screen provided in the vehicle to control thecontents of the display of the display device so that a plurality ofdisplay screens are sequentially displayed, the display controllercomprising a switch for fixing the display screen of the display deviceto a specific display screen so that the contents of the display arecontrolled to fix the display screen of the display device to thespecific display screen in accordance with the operation of the switch.

[0026] Now, the present invention according to the first aspect will bedescribed below by referring to FIGS. 1, 2 and 4.

[0027] According to the first aspect of the present invention, when thedisplay screen of a display device is shifted from a monitor displayscreen 11 shown in FIG. 1(a) to a trouble display screen 21 shown inFIG. 2(a), if a switch means 21 f on the trouble display screen 21 isoperated, the display screen will be fixed to the trouble display screen21 for a prescribed time (for instance, 2 minutes). Further, the displayscreen may be kept fixed to a trouble display screen 21′ until a releaseor restart switch means 21 h on the trouble display screen 21′ shown inFIG. 2(b) is operated. Further, as shown in FIG. 4, when the monitordisplay screen 11 and trouble display screens 21, 22 and 23 arecyclically displayed, if the switch means 21 f on the specific troubledisplay screen shown in FIG. 1(a) is operated, the display screen willbe fixed to the specific trouble display screen 21.for a prescribed time(for instance, 2 minutes). Further, as shown in FIGS. 2(a) and 2(b), thedisplay screen may be kept fixed to the trouble display screen 21′ untilthe release or restart switch means 21 h on the trouble display screen21′ is operated.

[0028] Still further, when the trouble display screen 21 is currentlydisplayed as shown in FIG. 4, a switch means on the trouble displayscreen 21 which is currently displayed is operated so that the troubledisplay screen 21 may be shifted to the trouble display screen 22 or 23which will be displayed to fix the display screen to the trouble displayscreen 22 or 23. Further, when the trouble display screen 23 ispresently displayed in FIG. 4, a switch means on the trouble displayscreen 23 which is presently displayed is operated so that the troubledisplay screen 23 may be shifted to the trouble display screen 22 or 21which has been already displayed to fix the display screen to thetrouble display screen 22 or 21.

[0029] The display screen may be fixed not to the trouble display screenbut to the monitor display screen 11.

[0030] When the monitor display screen 11 is currently displayed in FIG.4, a switch means on the monitor display screen 11 which is currentlydisplayed is operated so that the display screen may be fixed to themonitor display screen 11 which is currently displayed. Further, whenthe trouble display screen 23 is currently displayed in FIG. 4, theswitch means on the trouble display screen 23 which is displayed atpresent is operated so that the display screen may be shifted to themonitor display screen 11 which will be displayed in future and fixed tothe monitor display screen 11. When the trouble display screen 21 iscurrently displayed in FIG. 4, the switch means on the trouble displayscreen 21 which is displayed at present is operated so that the displayscreen may be shifted to the monitor display screen 11 which has beenalready displayed and fixed to the monitor display screen 11.

[0031] Further, when the monitor display screen 11 is currentlydisplayed in FIGS. 1(a), 1(b) and 1(c), the switch means on the monitordisplay screen 11 which is currently displayed is operated so that thedisplay screen may be fixed to the monitor display screen which iscurrently displayed. Further, when the monitor display screen 11 iscurrently displayed in FIGS. 1(a), 1(b) and 1(c), the switch means onthe monitor display screen 11 which is displayed at present is operatedso that the display screen may be shifted to a monitor display screen 12which will be displayed in future and fixed to the monitor displayscreen 12. Further, when the monitor display screen 11 is currentlydisplayed in FIGS. 1(a), 1(b) and 1(c), the switch means on the monitordisplay screen 11 which is displayed at present is operated so that thedisplay screen may be shifted to a monitor display screen 13 which hasbeen already displayed and fixed to the monitor display screen 13.

[0032] According to the first aspect of the present invention, since thedisplay screen is fixed to the display of the specific display screen,the operator can completely and sufficiently recognize the contents ofthe display of the specific display screen.

[0033] In order to achieve the first object, according to a secondaspect of the present invention, there is provided a display controllerfor a display device of a vehicle having the display device provided inthe vehicle to display a monitor display screen for displaying thestates of the respective parts of the vehicle and a trouble generated inthe vehicle so that the contents of the display of the display deviceare controlled to cyclically display a plurality of kinds of troubles onthe monitor display screen, when the plural troubles are generated inthe vehicle, the display controller comprising a switch for fixing thetrouble display of the monitor display screen, wherein the contents ofthe display of the display device are controlled so that the troubledisplay of the monitor display screen is fixed to a trouble displaywhich is currently displayed in accordance with the operation of theswitch.

[0034] The present invention according to the second aspect will bedescribed below with reference to FIGS. 1(a), 1(b), 1(c), 2(a) and 2(b)and 5.

[0035] According to the second aspect of the present invention, as shownin FIG. 5, when the trouble display screens 21, 22 and 23 are cyclicallydisplayed on a part of the monitor display screen 11, if the switchmeans 21 f on the trouble display screen 21 shown in FIG. 1(a) isoperated, the display screen will be fixed to the specific troubledisplay screen 21 for a prescribed time (for instance, two minutes).Further, the display screen may be kept fixed to the trouble displayscreen 21′ until the release or restart switch means 21 h on the troubledisplay screen 21′ shown in FIG. 2(b) is operated.

[0036] According to the second aspect of the present invention, sincethe contents of the display of a part on the monitor display screen 11are fixed to the specific trouble display screen 21, the operator cancompletely recognize the contents of the display of the specific troubledisplay screen 21.

[0037] In order to achieve the second object, according to a thirdaspect of the present invention, there is provided a display controllerfor a display device of a vehicle having the display device fordisplaying a display screen provided in the vehicle to control thecontents of the display of the display device so that a plurality ofdisplay screens are sequentially displayed, the display controllercomprising a switch for returning the display screen of the displaydevice to a specific display screen so that the contents of the displayare controlled to return the display screen of the display device to thespecific display screen in accordance with the operation of the switch.

[0038] Now, the present invention according to the third aspect will bedescribed below by referring FIGS. 2(a), 2(b), 8 and 9.

[0039] According to the third aspect of the present invention, as shownin FIG. 9, when the monitor display screen 11 and the trouble displayscreens 21, 22 and 23 are cyclically displayed, if a switch means 21 gon the trouble display screen 21 shown in FIG. 1(a) is operated, thedisplay screen of the display device will be returned to the monitordisplay screen 11 from the trouble display screen 21 and the monitordisplay screen 11 is displayed for a prescribed time (for instance, fiveminutes). Further, a switch means 21 e on the trouble display screen 21′shown in FIG. 2(b) is operated so that the display screen maybe keptreturned to the monitor display screen 11.

[0040] According to the third aspect of the present invention, as shownin FIG. 8, when the monitor display screen 11 and the trouble displayscreen 21 are alternately displayed, if the switch means 21 g on thetrouble display screen 21 shown in FIG. 1(a) is operated, the displayscreen of the display device will be returned to the monitor displayscreen 11 from the trouble display screen 21 and the monitor displayscreen 11 is displayed for a prescribed time (for instance, 5 minutes).Further, the switch means 21 e on the trouble display screen 21′ shownin FIG. 2(b) is operated so that the display screen may be kept returnedto the monitor display screen 11.

[0041] Further, the display screen may not be returned to the monitordisplay screen from the trouble display screen, and may be returned toother monitor screen from the monitor display screen.

[0042] Specifically described, when the monitor display screen 12 iscurrently displayed, in FIGS. 1(a), 1(b) and 1(c), as witch means on themonitor display screen 12 which is displayed at present is operated sothat the display of the monitor display screen 12 may be returned tothat of the monitor display screen 11. Further, when the monitor displayscreen 13 is currently displayed in FIGS. 1(a), 1(b) and 1(c), a switchmeans on the monitor display screen 13 which is presently displayed isoperated so that the display of the monitor display screen 13 may bereturned to that of the monitor display screen 11.

[0043] The display screen may be returned not to the monitor displayscreen, but to the trouble display screen.

[0044] According to the third aspect of the present invention, even whenthe trouble is generated in the vehicle of the construction machine orthe like, the monitor display screen and the trouble display screens aresequentially displayed or a plurality of monitor display screens aresequentially displayed so that one monitor display screen is displayedonly for a short period, the display screen is returned to theabove-described one monitor display screen. Thus, the operating state ofthe vehicle can be sufficiently recognized. Furthermore, even when thetrouble is generated in the vehicle of the construction machine or thelike, the monitor display screen and the trouble display screens aresequentially displayed so that one trouble display screen is displayedonly for a short period, the display screen is returned to theabove-described one trouble display screen. Therefore, the contents ofthe trouble of the vehicle can be completely recognized.

[0045] In order to attain the second object, according to a fourthaspect of the present invention, there is provided a display controllerfor a display device of a vehicle having the display device provided inthe vehicle to display a monitor display screen for displaying thestates of the respective parts of the vehicle and trouble displayscreens for displaying troubles generated in the vehicle so that thecontents of the display of the display device are controlled tocyclically display on the display device the monitor display screen anda plurality of kinds of trouble display screens, when the pluraltroubles are generated in the vehicle, wherein the contents of thedisplay of the display device are controlled so that the monitor displayscreen is displayed in arbitrary parts of the displaying intervals of aplurality of kinds of trouble display screens.

[0046] The present invention according to the fourth aspect will bedescribed below with reference to FIGS. 4 and 10.

[0047] According to the fourth aspect of the present invention, when themonitor display screen 11 and the trouble display screens 21, 22 and 23are cyclically displayed as shown in FIG. 4, the display of the displaydevice is controlled so that the monitor display screen 11 is displayedon the way of each interval (designated by an arrow mark C and an arrowmark D) for displaying these plural trouble display screens 21, 22 and23. For example, as shown in FIG. 10, not only the monitor displayscreen 11 is displayed between the trouble display screen 23 and thetrouble display screen 21, but also the monitor display screen 11 isdisplayed between the trouble display screen 21 and the trouble displayscreen 22 and the monitor display screen 11 is displayed between thetrouble display screen 22 and the trouble display screen 23.

[0048] According to the fourth aspect of the present invention, sincethe number of times of chances of displaying the monitor display screens11 is increased, and accordingly, even when the trouble is generated inthe vehicle of the construction machine or the like, the state of thevehicle can be completely recognized.

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] FIGS. 1(a), 1(b) and 1(c) are diagrams showing examples to whichmonitor display screens according to embodiments move.

[0050] FIGS. 2(a) and 2(b) are diagrams showing the contents of thedisplay of trouble display screens according to the embodiments.

[0051]FIG. 3 shows diagrams for illustrating that the monitor displayscreen and the trouble display screen are alternately displayed.

[0052]FIG. 4 shows diagrams for illustrating that the monitor displayscreen and a plurality of trouble display screens are cyclicallydisplayed.

[0053]FIG. 5 shows diagrams for illustrating that plural troubles arecyclically displayed on a part of the monitor display screen.

[0054]FIG. 6 is a diagram showing a flowchart of the embodiments.

[0055]FIG. 7 is a diagram showing a flowchart of the embodiments.

[0056]FIG. 8 is a diagram for explaining the embodiment in which, whenthe monitor display screen and the trouble display screen arealternately displayed, a display screen can be arbitrarily returned tothe monitor display screen.

[0057]FIG. 9 is a diagram for explaining the example in which, when themonitor display screen and a plurality of trouble display screens arecyclically displayed, a display screen can be arbitrarily returned tothe monitor display screen.

[0058]FIG. 10 shows the embodiment in which the monitor display screen,the first trouble display screen, the monitor display screen, the secondtrouble display screen, the monitor display screen and the third troubledisplay screen are cyclically displayed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Now, referring to the accompanying drawings, embodiments of adisplay controller for a display device of a vehicle according to thepresent invention will be described below.

[0060] In the embodiments, a construction machine such as a hydraulicshovel, a wheel loader is employed as a vehicle.

[0061] A monitor panel as a display device is provided in the driver'sroom of a construction machine. On the outer surface of the monitorpanel, a display screen and a group of switches comprising operatingswitches are arranged. A monitor controller is contained in the monitorpanel.

[0062] The states of respective parts such as the amount of remainingfuel of the engine of the construction machine, the temperature ofhydraulic oil of a working machine, the temperature of coolant of theengine, the oil pressure of the engine, etc. are detected by sensorsprovided in the respective parts of the construction machine. Thesignals detected by the sensors are inputted to the monitor controllerof the monitor panel.

[0063] The monitor controller collects the detected values of thesensors detected by the sensors and generates error codes when thedetected values of the sensors reach abnormal values. Then, the monitorcontroller displays error codes indicating the current state of theconstruction machine such as the temperature of the coolant and thespecific trouble state of the construction machine such as thedeterioration of the engine oil n the display screen of the monitorpanel.

[0064] Further, a group of the operating switches of the monitor panelare operated so that control data for controlling the traveling deviceof the construction machine or the working machine is generated in themonitor controller. The control data is outputted to an external partfrom the monitor controller and the driving of the construction machineis controlled in accordance with the control data. For instance, anysetting switch of the group of operating switches is operated so thatthe relation between the manipulated variable of an operating lever forthe working machine and the amount of work of the working machine, thatis, a work mode can be set to any one of a “heavy drill”, a “drill”, an“adjustment” and a “micro-operation”. Further, any setting switch of thegroup of operating switches is operated so that the capacity of ahydraulic pump and the capacity of a traveling hydraulic motor arecontrolled. Thus, the transmission position of the hydraulic motor, thatis, the travel speed of a vehicle body can be selectively set to any oneof “high speed (Hi)” “middle speed (Mi)” and “low speed (Lo)”.

[0065] First Embodiment

[0066] The display screens of a monitor panel according to embodimentsare illustrated in FIGS. 1(a), 1(b) and 1(c).

[0067] FIGS. 1(a), 1(b) and 1(c) shows monitor screens 11, 12 and 13 formonitoring and displaying the operating states of a constructionmachine.

[0068] On the monitor panel, prescribed positions of the displayedscreens 11, 12 and 13 are touched so that the display screens can beshifted to other display screens.

[0069] Specifically, when an engine key is switched on to turn on apower, the display screen of the monitor panel is shifted to a monitordisplay screen 11 shown in FIG. 1(a) via an initial screen.

[0070] The monitor controller controls the contents of the display todisplay the current state of the construction machine on the monitorscreen 11 in accordance with the signals detected by the respectivesensors.

[0071] As shown in FIG. 1(a), on the monitor display screen 11 areprovided a display part 11 a for displaying the amount of currentlyremaining fuel, a display part 11 b for displaying the currenttemperature of the hydraulic oil of the working machine, a display part11 c for displaying the current temperature of the coolant of theengine, a display part 11 d for displaying the current oil pressure ofthe engine, etc. An operator visually recognizes the display parts 11 ato 11 d of the monitor display screen 11 so that the operator canrecognize the conditions of the respective parts of the constructionmachine. In addition, a currently selected work mode and a currentlyselected transmission position (travel speed) can be also displayed onthe monitor display screen 11.

[0072] When a button 11 e on the monitor display screen 11 is operated,the monitor display screen 11 is shifted to a next monitor displayscreen 12 shown in FIG. 1(b). As shown in FIG. 1(b), on the monitordisplay screen 12 are arranged a display part 12 a for displaying thepresent temperature of oil of an engine, a display part 12 b fordisplaying the present temperature of oil of a PTO shaft, a display part12 c for displaying the present voltage of a board-net, a display part12 d for displaying the present voltage of a battery, etc.

[0073] Further, when a button 12 e on the monitor display screen 12 isoperated, the monitor display screen 12 is shifted to a next monitordisplay screen 13 shown in FIG. 1(c). As shown in FIG. 1(c) on themonitor display screen 13, are arranged a display part 13 a fordisplaying the present amount of hydraulic oil of the working machine, adisplay part 13 b for displaying the present amount of oil of theengine, a display part 13 c for displaying the present amount of greaseof CLS, a display part 13 d for displaying the present amount of greaseof SLS or the like.

[0074] Further, when a button 13 e on the monitor display screen 13 isoperated, the monitor display screen 13 is returned to the first monitordisplay screen 11 shown in FIG. 1(a). If the same operations are carriedout after that, the same transitions will be repeated. As describedabove, the monitor display screens are sequentially and cyclicallyshifted from 11 and 12 to 13, so that all the states of the constructionmachine can be recognized.

[0075] Further, the monitor display screens are not shifted to othermonitor display screens in prescribed order by a manual operation, butselecting buttons for selecting specific monitor display screens may beprovided so that the monitor display screen can be shifted to thespecific monitor display screen selected by the selecting button. Forinstance, when the selecting button on the monitor display screen 11 isoperated, the monitor display screen 11 is not shifted to the monitordisplay screen 12 shown in FIG. 1(b), but can be shifted to the monitordisplay screen 13 shown in FIG. 1(c).

[0076] When the detected value of each sensor provided in each part ofthe construction machine reaches an abnormal value, an error codecorresponding to the abnormality is generated in the monitor controllerand the display screen of the monitor panel is automatically shifted toa trouble display screen for displaying a trouble such as a failure fromthe present monitor display screens 11, 12 and 13 shown in FIGS. 1(a),1(b) and 1(c).

[0077] For instance, when a trouble or problem such as a failure isgenerated in a pump controller during the display of the monitor displayscreen 11 shown in FIG. 1(a) on the monitor panel, the monitor displayscreen 11 is shifted to a trouble display screen 21 shown in FIG. 1(a).In the trouble display screen 21, a trouble display showing the contentsof “Problem pump controller” is displayed.

[0078] As shown in FIG. 1(a), on the trouble display screen 21 (calledit a first trouble display screen 21), an icon 21 a corresponding to thecontents of the trouble, an error message 21 b indicating the contentsof the trouble, the treatment contents 21 c for treating the trouble andan error code 21 d are displayed as a first trouble display. Inaddition, on the first trouble display screen 21, a cancel button 21 e,a pause button 21 f and a jump button 21 g are arranged.

[0079] The operator visually recognizes the first trouble display of thefirst trouble display screen 21 so that the operator can recognize thedetail of the first trouble (“Problem pump controller”) generated in theconstruction machine.

[0080] The monitor display screen 11 shown in FIG. 1(a) and the troubledisplay screen 21 shown in FIG. 1(a) are alternately displayed atprescribed intervals, for example, at intervals of 5 seconds. Thus,while the operator recognizes the contents of the trouble generated inthe construction machine, he can continuously perform the operation ofthe construction machine.

[0081] When a trouble (called it a second trouble) except the firsttrouble, for instance “Engine coolant temperature trouble” is generated,the present monitor display screen 11 is shifted to a second troubledisplay screen 22 on which the second trouble is displayed as shown inFIG. 3. As shown in FIG. 3, on the second trouble display screen 22, anicon 22 a corresponding to the contents of the trouble, an error message22 b indicating the contents of the trouble, the treatment contents 22 cfor treating the trouble and an error code 22 d are displayed as asecond trouble display. In addition, on the second trouble displayscreen 22, a cancel button 22 e, a pause button 22 f and a jump button22 g are arranged. Then, the monitor display screen 11 and the secondtrouble display screen 22 are alternately displayed at prescribedintervals. When a third trouble different from the first trouble and thesecond trouble is similarly generated, a third trouble display screen 23on which the third trouble is displayed and the monitor display screen11 are alternately displayed.

[0082] In the construction machine, a plurality of problems or troublesmay be possibly generated at the same time. For instance, three kinds oftroubles maybe generated. If three kinds of troubles including a firsttrouble, a second trouble and a third trouble are generated while themonitor display screen 11 shown in FIG. 1(a) is displayed on the monitorpanel, the monitor display screen 11, the first trouble display screen21 on which the first trouble is displayed, a second trouble displayscreen 22 on which the second trouble is displayed and a third troubledisplay screen 23 on which the third trouble is displayed will becyclically displayed as shown in FIG. 4. In other words, the monitordisplay screen 11, the first trouble display screen 21, the secondtrouble display screen 22 and the third trouble display screen 23 aredisplayed at intervals of, for instance, 5 seconds.

[0083] In this case, a plurality of trouble display screens can beshifted in regular order of the first trouble display screen 21, thesecond trouble display screen 22 and the third trouble display screen 23by a manual operation in a similar manner to that of the monitor displayscreens.

[0084] The trouble display screens are not shifted or changed inprescribed order by a manual operation, but selecting buttons forselecting specific trouble display screens may be provided so that thetrouble display screen can be shifted to the specific trouble displayscreen selected by the selecting button. For instance, the selectingbutton on the first trouble display screen 21 is operated so that thefirst trouble display screen 21 is not shifted to the second troubledisplay screen 22, but can be shifted to the third trouble displayscreen 23.

[0085] Further when the monitor display screens and the trouble displayscreens are mixed together and sequentially displayed, one displayscreen may be manually shifted to a next display screen in prescribedorder, or one display monitor screen maybe selectively shifted to anarbitrary display screen by operating the selecting button.

[0086] Still further, when the monitor display screens and the troubledisplay screens are mixed together and sequentially displayed, theplural display screens may be automatically shifted or changed.

[0087] As described above, according to the present embodiments sincethe plural display screens are sequentially displayed on the same screenof the monitor panel, the state of the construction machine and manyinformation related to the abnormality or trouble can be displayed onthe screen of the monitor panel without decreasing the size ofindividual display parts, so that visual recognition characteristics canbe improved.

[0088] Second Embodiment

[0089] In the first embodiment, the monitor display screen is shifted ormoved to another display screen by the manual operation. However, themonitor display screen may be sequentially and automatically shifted orchanged in regular order of the monitor display screens 11, 12 and 13without performing a manual operation. Thus, an operator can recognizeall the information related to the inner state of the constructionmachine without manually operating the monitor panel.

[0090] As shown in FIG. 4, when a plurality of troubles are generated,the first trouble display screen 21 on which the first trouble isdisplayed, the second trouble display screen 22 on which the secondtrouble is displayed, and the third trouble display screen 23 on whichthe third trouble is displayed may be sequentially and automaticallydisplayed without carrying out the manual operation. That is, forinstance, the monitor display screen 11, the first trouble displayscreen 21, the second trouble display screen 22 and the third troubledisplay screen 23 are displayed at intervals of 5 seconds. Thus, theoperator can recognize all information related to the abnormality ortrouble of the construction machine without manually operating themonitor panel.

[0091] Further, when the monitor display screen and the trouble displayscreens are sequentially displayed in a mixed manner, the plural displayscreens may be automatically shifted or changed.

[0092] As described above, according to the second embodiment, even whenboth the hands of the operator are bound to an operating lever or thelike during the operation of the construction machine, and accordingly,the operator cannot freely move the hands, he or she can easilyrecognize all information necessary for the operation.

[0093] When the monitor display screen 11 and the trouble display screen21 are alternately displayed, or when the monitor display screen 11, andthe trouble display screens 21, 22 and 23 are cyclically displayed, theoperator is forced to recognize the contents of the trouble displayscreen21 in short time (for instance, 5 seconds). Therefore, theoperator cannot completely recognize the contents of display on thetrouble display screen 21. Now, an embodiment for completely graspingthe contents of a generated trouble will be described below.

[0094] Third Embodiment

[0095] A third embodiment will be described by checking a flowchartshown in FIG. 6

[0096] In the third embodiment, a case in which a monitor display screen11 shown in FIG. 1(a) and a trouble display screen 21 shown in FIG. 1(a)are alternately displayed on the monitor panel is supposed to be used(steps 101 and 102). When the display screen of the monitor panel isshifted to the trouble display screen21 (step 102), if a pause button 21f on the trouble display screen 21 is touched as shown in FIG. 1(a)(step 103), the display screen of the monitor panel will be fixed to thetrouble display screen 21 for a prescribed time (for instance, 2minutes) (step 104). Then, when the prescribed time elapses, the displayscreen of the monitor panel is returned again to the monitor displayscreen 11 (step 101).

[0097] In another embodiment, if a pause button 21 f on the troubledisplay screen 21 is touched as shown in FIG. 1(a) (step 103), thedisplay screen of the monitor panel will be shifted to a trouble displayscreen 21′ shown in FIG. 2(b), the pause button 21 f will be changed toa restart button 21 h and the display color of the button 21 h will bechanged to red (it is shown by broken lines). Then, the display screenis fixed to the trouble display screen 21′ (step 104) until the restartbutton 21 h on the trouble display screen 21′ is operated. When therestart button 21 h on the trouble display screen 21′ is touched, thedisplay screen of the monitor panel is returned again to the monitordisplay screen 11 (step 101).

[0098] As described above, according to the third embodiment, since thedisplay screen is fixed to the display of the trouble display screen 21the operator can completely recognize the contents of the display of thetrouble display screen 21.

[0099] Fourth Embodiment

[0100] A fourth embodiment of the present invention will be describedbelow by checking the flowchart shown in FIG. 6.

[0101] In the fourth embodiment, it is supposed that a case in which amonitor display screen 11, a first trouble display screen 21, a secondtrouble display screen 22 and a third trouble display screen 23 arecyclically displayed on a monitor panel as shown in FIG. 4 is employed(steps 101 and 102). When the display screen of the monitor panel isshifted to, for example, the first trouble display screen 21 (step 102),if a pause button 21 f on the first trouble display screen 21 is touchedas shown in FIG. 1(a) (step 103), the display screen of the monitorpanel will be fixed to the first trouble display screen 21 for aprescribed time (for instance, 2 minutes) (step 104). Then, when theprescribed time elapses, the display screen of the monitor panelsequentially shifts again to the next second trouble display screen 22and the third trouble display screen 23, and then returns to the monitordisplay screen 11 (step 101).

[0102] In another embodiment, if a pause button 21 f on the troubledisplay screen 21 is operated as shown in FIG. 1(a) (step 103), thedisplay screen of the monitor panel will be shifted to a trouble displayscreen 21′ shown in FIG. 2(b), the pause button 21 f will be changed toa restart button 21 h and the display color of the button 21 h will bechanged to red (it is shown by broken lines). Then, the display screenis fixed to the trouble display screen 21′ (step 104) until the restartbutton 21 h on the trouble display screen 21′ is operated. When therestart button 21 h on the trouble display screen 21′ is touched, thedisplay screen of the monitor panel is sequentially shifted to the nextsecond trouble display screen 22 and the third trouble display screen23, and then returned to the monitor display screen 11 (step 101).

[0103] As described above, according to the fourth embodiment, since thedisplay screen is fixed to the display of the trouble display screen 21,an operator can satisfactorily recognize the contents of the display ofthe trouble display screen 21.

[0104] In the above-described third and fourth embodiments, it issupposed that the case in which, when the trouble display screen 21 iscurrently displayed, the display screen is fixed the current troubledisplay screen 21 is used.

[0105] However, when the first trouble display screen 21 is currentlydisplayed, a switch means on the first trouble display screen 21 whichis displayed at present may be operated to shift the display screen tothe second trouble display screen 22 or the third trouble display screen23 which will be displayed and to fix the display screen to the secondtrouble display screen or the third trouble display screen 23. Further,when the third trouble display screen 23 is currently displayed in FIG.4, a switch means on the third trouble display screen 23 which ispresently displayed may be operated to shift the display screen to thesecond trouble display screen 22 or the first trouble display screen 21which has been already displayed and to fix the display screen to thesecond trouble display screen 22 or the first trouble display screen 21.

[0106] In addition, the display screen may be fixed not to the troubledisplay screen, but to the monitor display screen 11.

[0107] That is to say, when the monitor display screen 11 is currentlydisplayed in FIG. 4, a switch means on the monitor display screen 11which is currently displayed may be operated to fix the display screento the current monitor display screen 11. Further, when the thirdtrouble display screen 23 is currently displayed in FIG. 4, the switchmeans on the third trouble display screen 23 which is presentlydisplayed may be operated to shift the display screen to the monitordisplay screen 11 which will be displayed in future and fix the displayscreen to the monitor display screen 11. In FIG. 4, when the firsttrouble display screen 21 is currently displayed, the switch means onthe first trouble display screen 21 which is currently displayed may beoperated to shift the display screen to the monitor display screen 11which has been already displayed and fix the display screen to themonitor display screen 11.

[0108] Still further, when a plurality of monitor display screens aredisplayed without showing the trouble display screen, a display screenmay be fixed to a specific monitor screen.

[0109] Specifically, when the monitor display screen 11 is currentlydisplayed in FIGS. 1(a), 1(b) and 1(c), the switch means on the monitordisplay screen 11 which is currently displayed may be operated to fix orsecure the display screen to the current monitor display screen 11.Further, when the monitor display screen 11 is presently displayed inFIGS. 1(a), 1(b) and 1(c), a switch means on the monitor display screen11 which is displayed at present may be operated to shift the displayscreen to a monitor display screen 12 which will be displayed and fixthe display screen to the monitor display screen 12. Still further, whenthe monitor display screen 11 is currently shown, a switch means on themonitor display screen 11 which is displayed at present may be operatedto shift the display screen to a monitor display screen 13 which hasbeen already displayed and fix the display screen to the monitor displayscreen 13.

[0110] As described above, according to the second embodiment, since thedisplay screen is fixed to the display of the specific display screen,the operator can completely recognize the contents of the display of thespecific display screen.

[0111] According to the above-described third and fourth embodiments,although the contents of the trouble are displayed on the screendifferent from the monitor display screen, it is to be understood thatthe contents of the trouble may be displayed on the monitor displayscreen.

[0112] Fifth Embodiment

[0113] A fifth embodiment will be described below by checking andreferring to the flowchart shown in FIG. 6.

[0114] In the fifth embodiment, it is supposed that a case in which thecontents of a trouble are displayed in a part of a monitor displayscreen 11, as shown in FIG. 5 is used. That is, parts corresponding todisplay parts 11 c and lid of display parts 11 a to lid on the monitordisplay screen 11 are cyclically changed to monitor displays 11 c andlid, a first trouble display 21, a second trouble display 22 and a thirdtrouble display 23 (steps 101 and 102). When a part of a display part onthe monitor display screen 11 is shifted to, for instance, the firsttrouble display 21 (step 102), if a pause button 21 f on the firsttrouble display 21 is touched (step 103) as shown in FIG. 1(a), a partof the display part on the monitor display screen 11 will be fixed tothe first trouble display 21 (step 104) for a prescribed time (forinstance, 2 minutes). Then, when the prescribed time elapses, thedisplay part on a part of the monitor display screen 11 is sequentiallyshifted to a next second trouble display 22 and a third trouble display23 and returned to the monitor displays 11 c and lid (step 101).

[0115] In another embodiment, if a pause button 21 f on the firsttrouble display 21 is touched as shown in FIG. 1(a) (step 103), thedisplay part on a part of the monitor display screen 11 will be shiftedto a first trouble display 21′ shown in FIG. 2(b), the pause button 21 fwill be changed to a restart button 21 h and the display color of thebutton 21 h will be changed to red (it is shown by broken lines). Then,the display screen is fixed to the first trouble display 21′ (step 104)until the restart button 21 h on the trouble display 21′ is operated.When the restart button 21 h on the first trouble display 21′ istouched, the display part on a part of the monitor display screen 11 issequentially shifted to the next second trouble display 22 and the thirdtrouble display 23, and then returned to the monitor displays 11 c and11 d (step 101).

[0116] As described above, according to the fifth embodiment, since apart of the display parts on the monitor screen 11 is fixed to thespecific trouble display 21, an operator can sufficiently recognize thecontents of the trouble display 21.

[0117] In the above-described fifth embodiment, as shown in FIG. 5, thefirst trouble display 21, the second trouble display 22 and the thirdtrouble display 23 are displayed on parts corresponding to the displayparts 11 c and 11 d of the display parts 11 a to 11 d on the monitordisplay screen 11.

[0118] However, on the monitor display screen 11, positions where thefirst trouble display 21, the second trouble display 22 and the thirdtrouble display 23 are displayed can be arbitrarily set.

[0119] For example, the first trouble display 21, the second troubledisplay 22 and the third trouble display 23 may be displayed in theparts corresponding to the display parts 11 a and 11 b of the displayparts 11 a to 11 d on the monitor display screen 11.

[0120] Further, the first trouble display 21, the second trouble display22 and the third trouble display 23 may be displayed on the partscorresponding to the display parts 11 c and lid of the display parts 11a to lid on the monitor display screen 11 and the monitor displays 11 cand 11 d may be displayed on the parts corresponding to the displayparts 11 a and 11 b.

[0121] Further, the first trouble display 21, the second trouble display22 and the third trouble display 23 may be respectively displayed indifferent parts.

[0122] For example, when the first trouble display 21 is shown, thefirst trouble display 21 may be displayed on the parts corresponding tothe display parts 11 c and lid of the respective display parts 11 a to11 d on the monitor display screen 11. When the second trouble display22 is displayed, the second trouble display 22 may be displayed on theparts corresponding to the display parts 11 a and 11 b of the displayparts 11 a to 11 d on the monitor display screen 11.

[0123] As described in the first embodiment and the second embodiment,when the monitor display screen 11 and the trouble display screens 21,22 and 23 are sequentially displayed, the operator has only a fewchances to recognize the monitor display screen 11. Therefore, therearises a fear that the operator cannot satisfactorily understand thestate of the construction machine to cause a trouble in an operatingwork of the construction machine.

[0124] Now, there will be described below an embodiment in which, when aplurality of trouble display screens are sequentially displayed, thechances to recognize the monitor display screen are increased so thatthe operating work of the construction machine can be carried outwithout failure.

[0125] Sixth Embodiment

[0126] As shown in FIG. 4, when the monitor display screen 11, and thetrouble display screens 21, 22 and 23 are cyclically displayed, adisplay order is changed so that the monitor display screen 11 isdisplayed in prescribed parts (shown by arrow marks C and D) on the wayof respective intervals of display of the three kinds of trouble displayscreens 21, 22 and 23. Such a control of display can be readilyperformed by changing the contents of setting of a controller for amonitor.

[0127] For instance, as shown in FIG. 10, the monitor display screen 11,the first trouble display screen 21, the monitor display screen 12, thesecond trouble display screen 22, the monitor display screen 13 and thethird trouble display screen 23 are cyclically displayed.

[0128] Accordingly, when this display order is compared with the displayorder shown in FIG. 4, not only the monitor display screen 11 isdisplayed between the third trouble display screen 23 and the firsttrouble display screen 21, but also the monitor display screen 11 isdisplayed between the first trouble display screen 21 and the secondtrouble display screen 22 and the monitor display screen 11 is alsodisplayed between the second trouble display screen 22 and the thirdtrouble display screen 23 so that the number of chances to display themonitor display screen 11 is increased during one cycle. As describedabove, since time when the monitor display screen 11 is displayed islengthened during one cycle, even when any trouble is generated in theconstruction machine, the condition of the construction machine can becompletely recognized.

[0129] In FIG. 4, the monitor display screen 11 may be displayed only inthe interval between the first trouble display screen 21 and the secondtrouble display screen 22 as shown by the arrow mark C. Further, themonitor display screen 11 may be displayed only in the interval betweenthe second trouble display screen 22 and the third trouble displayscreen 23, as shown by the arrow mark D.

[0130] As described in the first embodiment and the second embodiment,when the plural monitor display screens are sequentially displayed, if atrouble or abnormality is generated, the trouble display screen 21 andthe monitor display screens 11, 12 and 13 will be sequentiallydisplayed, so that the operator has few chances to recognize the troubledisplay screen 21. Therefore, the operator cannot completely grasp thetrouble or abnormality of the construction machine. Accordingly, thereexists a fear that the detection of a failure of the constructionmachine may be possibly delayed.

[0131] Now, there will be described below an embodiment, in which, whena plurality of monitor display screens are sequentially displayed, thenumber of chances to recognize the trouble display screen is increasedso that the failure of the construction machine can be detected withoutdelay.

[0132] Seventh Embodiment

[0133] Referring to FIGS. 1(a), 1(b) and 1(c), when the monitor displayscreens 11, 12 and 13 are sequentially displayed, if any trouble isgenerated, the display of the display device will be controlled to showthe trouble display screen 21 on the way of respective intervals ofdisplay of the plural kinds of monitor display screens 11, 12 and 13.For example, the trouble display screen 21, the monitor display screen11, the trouble display screen 21, the monitor display screen 12, thetrouble display screen 21 and the monitor display screen 13 arecyclically displayed.

[0134] According to the seventh embodiment, even when the plural kindsof monitor display screens 11, 12 and 13 are sequentially displayed,since the number of chances to display the trouble display screen 21 isincreased, the trouble or abnormality of a vehicle can be sufficientlyrecognized and the failure of the construction machine can be detectedwithout delay.

[0135] Thus, even when the trouble is generated in the constructionmachine, the operator of the construction machine can continuouslyoperate the construction machine, while paying his attention to thetrouble.

[0136] However, when the monitor display screen 11 and the troubledisplay screen 21 are alternately displayed, or when the monitor displayscreen 11 and the trouble display screens 21, 22 and 23 are cyclicallydisplayed, unfortunately, the operator can continuously recognize thecontents of the display of the monitor display screen 11 with his eyesonly for a short time (for instance, five minutes). Further, when aplurality of the trouble display screens are displayed, the operatorcannot visually recognize the monitor display screen 11 for a long timewhen the trouble display screens 21, 22 and 23 are displayed. Thus, anembodiment in which the state of the construction machine can becompletely grasped will be described below.

[0137] Eighth Embodiment

[0138] An eighth embodiment of the present invention will be describedbelow by checking and referring to a flowchart shown in FIG. 7.

[0139] In the eighth embodiment of the invention, it is supposed that acase in which a monitor screen 11, a first trouble display screen 21, asecond trouble display screen 22 and a third trouble display screen 23are cyclically displayed on a monitor panel is employed (steps 201 and202). For example, when the display screen of the monitor panel isshifted to the first trouble display screen 21 (step 202), if a jumpbutton 21 g on the first trouble display screen 21 is touched as shownin FIG. 1(a) (step 203), the display screen of the monitor panel will bereturned to the initial monitor display screen 11 as shown by an arrowmark 31 indicated by broken lines in FIG. 9 and the display screen isfixed to the monitor display screen 11 for a prescribed time (forinstance, 5 minutes) (step 204). Then, when the prescribed time elapses,the display screen of the monitor panel shifts to the first troubledisplay screen 21 from the monitor display screen 11 as shown by anarrow mark 32 indicated by broken lines in FIG. 9. Subsequently, thedisplay screen is sequentially shifted to the second trouble displayscreen 22 and the third trouble display screen 23 (step 205), and then,returned to the monitor display screen 11 (step 201).

[0140] When a jump button 22 g on the second trouble display screen 22is touched (step 203) while the second trouble display screen 22 isdisplayed on the monitor panel, the display screen of the monitor panelis returned to the initial monitor screen 11 as shown by an arrow mark33 indicated by broken lines in FIG. 9 and the display screen is fixedto the monitor display screen 11 for a prescribed time (for instance, 5minutes) (step 204). When the prescribed time elapses, the displayscreen of the monitor panel is shifted to the second trouble displayscreen 22 as shown by an arrow mark 34 shown by broken lines in FIG. 9.Similarly, when a jump button 23 g on the third trouble display screen23 is touched (step 203) while the third trouble display screen 23 isdisplayed on the monitor panel, the display screen of the monitor panelis returned to the initial monitor screen 11 as shown by an arrow mark35 indicated by broken lines in FIG. 9 and the display screen is fixedto the monitor display screen 11 for a prescribed time (for instance, 5minutes) (step 204). When the prescribed time elapses, the displayscreen of the monitor panel is shifted to the third trouble displayscreen 23 as shown by an arrow mark 36 shown by broken lines in FIG. 9.

[0141] In another embodiment, a cancel button 21 e on the second troubledisplay screen 21 is touched as shown in FIG. 1(a), so that the displayscreen of the monitor panel can be kept returned to the monitor displayscreen 11 from the first trouble display screen 21. In this case, whenthe engine key is restarted, a cyclic display shown in FIG. 9 can beresumed by carrying out a special operation.

[0142] As described above, according to the eighth embodiment of thepresent invention, since the display screen of the monitor panel isreturned to the monitor display screen 11, the state of the constructionmachine can be carefully and thoroughly recognized even when any troubleis generated in the construction machine.

[0143] Ninth Embodiment

[0144] A ninth embodiment of the present invention will be describedbelow by checking and referring to the flowchart shown in FIG. 7.

[0145] In the ninth embodiment of the invention, it is supposed that acase in which a monitor display screen 11 and a trouble display screen21 are alternately displayed on a monitor panel as shown in FIG. 8 isused (steps 201 and 202). For example, when the display screen of themonitor panel is shifted to the trouble display screen 21 (step 202), ifa jump button 21 g on the trouble display screen 21 is touched as shownin FIG. 1(a) (step 203), the display screen of the monitor panel will bereturned to the initial monitor display screen 11 as shown by an arrowmark 31 indicated by broken lines in FIG. 8 and the display screen isfixed to the monitor display screen 11 for a prescribed time (forinstance, 5 minutes) (step 204). Then, when the prescribed time elapses,the display screen of the monitor panel shifts to the trouble displayscreen 21 from the monitor display screen 11 as shown by an arrow mark32 indicated by broken lines in FIG. 8, and then, returned to themonitor display screen 11 (step 201).

[0146] In another embodiment, a cancel button 21 e on the troubledisplay screen 21 is touched as shown in FIG. 1(a), so that the displayscreen of the monitor panel can be kept returned to the monitor displayscreen 11 from the trouble display screen 21. In this case, when theengine key is restarted, an alternate display shown in FIG. 8 can beresumed by carrying out a special operation.

[0147] As described above, according to the ninth embodiment of thepresent invention, since the display screen of the monitor panel isreturned to the monitor display screen 11, the state of the constructionmachine can be carefully and thoroughly recognized.

[0148] According to the above-described eighth and ninth embodiments,although the display screen is returned to the monitor display screenfrom the trouble display screen, it is to be noted that the displayscreen may be returned from the monitor display screen to other monitorscreen.

[0149] Specifically stated, when a monitor screen 12 is currentlydisplayed in FIGS. 1(a), 1(b) and 1(c), a switch means on the monitordisplay screen 12 which is currently displayed may be operated to returnthe display screen to a monitor display screen 11. Further, when amonitor display screen 13 is currently displayed in FIGS. 1(a), 1(b) and1(c), a switch means on the monitor display screen 13 which is currentlydisplayed may be operated to return the display screen to the monitordisplay screen 11.

[0150] In this case, for example, if the monitor display screen 12 ispresently displayed, a switch means for selectively returning thedisplay screen to either the monitor display screen 11 or the monitordisplay screen 13 may be provided on the monitor display screen 12 whichis currently displayed to return the display screen to the arbitrarymonitor display screen 11 or 13, or a switch means for returning thedisplay screen to the specific monitor display screen 11 may be providedon the monitor display screen 12 which is currently displayed to returnthe display screen to the specific monitor display screen 11.

[0151] Besides, the display screen may be returned not to the monitordisplay screen, but to the trouble display screen.

[0152] An eighth embodiment and a ninth embodiment may be applied toboth a case in which the display screens of the monitor panel areautomatically and sequentially shifted or changed and a case in whichthe display screens are sequentially shifted by a manual operation. Whenthe display screens are sequentially shifted by the manual operation, inthe case that the present embodiment is applied, the number of theoperations of the buttons can be decreased, the labor of the operatorcan be reduced and the display screen can be rapidly switched to thespecific display screen.

[0153] As described above, according to the ninth embodiment of thepresent invention, even when the trouble is generated in theconstruction machine and the monitor display screen and the troubledisplay screen are alternately displayed, or a plurality of troubledisplay screens are sequentially displayed so that one monitor screen isdisplayed only for a short period, the display screen is returned to theabove-described one monitor display screen. Therefore, the operatingstate of the construction machine can be absolutely recognized. Further,even when the trouble is generated and the monitor screen and thetrouble display screens are sequentially displayed so that one troubledisplay screen is displayed only for a short period, the display screenis returned to the above-described one trouble display screen.Therefore, the contents of the trouble of the construction machine canbe completely recognized.

[0154] Tenth Embodiment

[0155] It is assumed that an “abnormality of the temperature of enginecoolant” (second trouble) is to be generated. In this case, as shown inFIG. 9, when the monitor display screen showing the “temperature of theengine coolant” is currently displayed on the monitor panel, if a buttonis pressed, the monitor display screen will be returned to the secondtrouble display screen 22 showing the abnormality related to thetemperature of the engine coolant.

[0156] That is, the temperature of the engine coolant is shown by agauge on the monitor display screen 11, however, this is the only thingthat the operator frequently neglects to continue an operation.

[0157] In the tenth embodiment, when the button is pressed, the monitordisplay screen is returned to the second trouble display screen 22related to the temperature of the engine coolant. Thus, the operator canbe excited to pay attention thereto.

[0158] Conversely, when the second trouble display screen 22 showing theabnormality of the temperature of the engine coolant is currentlydisplayed on the monitor panel, if the button is pushed, the secondtrouble display screen 22 will be returned to the monitor display screen11 related to the temperature of the engine coolant.

[0159] In other word, the operator cannot understand whether the currenttemperature shows a value near a normal value, or shows fataltemperature only by showing the trouble display screen 22 for thetemperature of the engine coolant.

[0160] In the present embodiment, when the button is pressed, thetrouble display screen is returned to the monitor display screen 11displaying the gauge for indicating the temperature of the enginecoolant, so that the operator can precisely grasp the currenttemperature and decide whether or not the operation is to becontinuously carried out.

[0161] The tenth embodiment can be applied to both a case in which thedisplay screens of the monitor panel can be automatically andsequentially shifted or changed and a case in which the display screensare sequentially shifted by the manual operation. When the presentembodiment is applied to the case in which the display screens aresequentially shifted by the manual operation, the number of operationsof the buttons can be decreased, the labor of the operator can bereduced and the display screen can be rapidly switched to the specificdisplay screen.

[0162] In the above-described embodiments, although the monitor panel isassumed to be mounted on the construction machine and is described, itis to be understood that the present invention is not limited thereto,and the present invention may be applied to a display device mounted onan arbitrary vehicle such as an ordinary automobile, or the like.

What is claimed is:
 1. A display device provided in a vehicle fordisplaying monitor display screens for displaying the state of each partof the vehicle or trouble display screens for displaying troublesgenerated in the vehicle, wherein a plurality of monitor displayscreens, a plurality of trouble display screens or a plurality ofdisplay screens including both the monitor display screens and thetrouble display screens are sequentially displayed on the same screen ofthe display device.
 2. A display device provided in a vehicle fordisplaying monitor display screens for displaying the state of each partof the vehicle or trouble display screens for displaying troublesgenerated in the vehicle, wherein a plurality of monitor displayscreens, a plurality of trouble display screens or a plurality ofdisplay screens including both the monitor display screens and thetrouble display screens are automatically and sequentially displayed onthe same screen of the display device.
 3. A display device provided in avehicle for displaying monitor display screens for displaying the stateof each part of the vehicle or trouble display screens for displayingtroubles generated in the vehicle, wherein a plurality of monitordisplay screens, a plurality of trouble display screens or a pluralityof display screens including both the monitor display screens and thetrouble display screens are automatically and sequentially displayed onthe same screen of the display device and the display screen of thedisplay device is fixed to a specific display screen when a switch unitis operated.
 4. A display device provided in a vehicle for displayingmonitor display screens for displaying the state of each part of thevehicle or trouble display screens for displaying troubles generated inthe vehicle, wherein a plurality of trouble display screens aresequentially displayed on the same screen of the display device and themonitor display screens are displayed on the same screen of the displaydevice at the intermediate parts of intervals for displaying the troubledisplay screens.
 5. A display device provided in a vehicle fordisplaying monitor display screens for displaying the state of each partof the vehicle or trouble display screens for displaying troublesgenerated in the vehicle, wherein a plurality of monitor display screensare sequentially displayed on the same screen of the display device, andthe trouble display screens are displayed on the same display screen ofthe display device at the intermediate parts of intervals for displayingthe monitor display screens.
 6. A display device provided in a vehiclefor displaying monitor display screens for displaying the state of eachpart of the vehicle or trouble display screens for displaying troublesgenerated in the vehicle, wherein a plurality of monitor displayscreens, a plurality of trouble display screens or a plurality ofdisplay screens including both the monitor display screens and thetrouble display screens are sequentially displayed on the same screen ofthe display device and the display screen of the display device isreturned to a specific display screen when a switch unit is operated. 7.A display device provided in a vehicle for displaying monitor displayscreens for displaying the state of each part of the vehicle or troubledisplay screens for displaying troubles generated in the vehicle,wherein a plurality display screens including both the monitor displayscreens and the trouble display screens are sequentially displayed onthe same screen of the display device, and when one of the monitordisplay screen and the trouble display screen is currently displayed,the display screen of the display device is returned to the otherdisplay screen related to the one display screen which is currentlydisplayed in accordance with the operation of a switch unit.